VISA staff in Britain have “lost sight” of what immigration rules are intended to achieve, according to a senior Scottish MP, who has described the refusal of a visa for an acclaimed Iranian illustrator of children’s books as “a nonsense”.

Stuart McDonald, the SNP’s front-bench spokesperson on immigration, was speaking after the campaigning group Scottish PEN condemned the Home Office’s refusal to grant a visa to Ehsan Abdollahi to attend the Edinburgh International Book Festival.